We report on the formation of high-quality ohmic contacts to p-type GaN (5 × 1017/cm3) using a Rh (100 nm) layer combined with a 3 nm thick Zn interlayer for high-power flip-chip light-emitting diodes (LEDs). The as-deposited sample produces a nonlinear behavior. However, the samples annealed at 430 and 530°C for 1 min in air become ohmic with a contact resistivity of ∼ 10-5 Ω cm2. Measurements show that the reflectivity of the samples annealed at 530°C is 73% at 460 nm. LEDs fabricated using the Zn/Rh contact layers give forward-bias voltages of 3.09-3.12 V at an injection current of 20 mA.
ASJC Scopus subject areas
- Chemical Engineering(all)
- Materials Science(all)
- Physical and Theoretical Chemistry
- Electrical and Electronic Engineering